Compound archery bows have become very popular for hunting and target shooting in recent years. These bows use a bowstring stretched between one or two cams. There are a variety of orientations of bowstrings, cams/pulleys, and (on some bows) cables, of which one or more types of bows is discussed herein as an example. It is thought that the inventive concepts discussed herein can be utilized on any compound archery bow, regardless of the orientation of the pulley(s), cables, cam(s), and/or bowstring while still utilizing the inventive concept herein. For this reason, the term, bowstring, refers herein to a single bowstring and/or a bowstring with one or more cables in addition to a bowstring connecting the cam(s) and/or pulley(s). The cams are attached to two limbs of the bow. The limbs of the bow are attached to a bow riser that typically has an arrow rest, a sight, and a grip for a user to grasp the handle of the bow. The bow riser and limbs typically are in an arch like formation with the bow strings stretching in between the two distal ends of the limbs from the cams and/or pulleys. In a dual cam bow there is a cam at each end of the limbs. In a single cam bow there is a cam typically at the lower limb and an idler pulley at the upper limb. Additionally, on some bows, stretched between the cam(s) and the pulley(s) is one or more cables, typically referred to as a cable. When the bow string is drawn back, the cams and pulleys rotate as the string winds out of the cams and the distal ends of the limbs are pulled closer together. As the bow string is being drawn, the draw weight or force applied to the string increases to a peak draw weight and reduces to a lower draw weight at the full draw position due to the eccentric geometry of the cams. This reduction in draw weight is known as a valley or draw weight let-off. When the drawn string is released, the string is wound back into the cams and the limbs rebound or retract outward imparting the energy stored in the limbs into the string.
Several different inventions have been developed to allow the user to stop the string from being released when the bow is at full draw. Typically these inventions involve placing some type of object in between the bow string and the bow riser to hold the bow string at a full draw position thus relieving a user from any further manual effort to retain the bowstring at full draw. An example of such a system is found at U.S. Pat. No. 4,886,039. However, systems that allow a user to hold a bow at full draw without manual effort typically do not allow a user to relieve some of the manual effort required to hold a bow at partial draw. The importance behind allowing a user to hold a bow at partial draw is illustrated in a hypothetical in which a user is hunting an animal such as a deer. The user generally waits until the deer is either not looking directly at the bow user or for when the deer's view of the bow user is obstructed by an object such as a tree. The bow user (or bow hunter) tries to remain still while in the animal's view because the animal is more likely to see the bow user if the bow user is moving while the animal is looking at the bow user. The user draws the bow string toward shooting position and if the deer (or other animal) looks at the user while the user is drawing the bowstring back, the bow user can stops drawing the bowstring further back and holds the bowstring at whatever draw position the bow string is at. This can be difficult, particularly in a bow with a high draw weight. When the deer (or other animal) is no longer looking toward the bow user, the user then draws the bow string further toward the fully drawn position. This starting and stopping of drawing of the bow string can occur multiple times depending on the behavior of the deer (or other animal) until the bow and bow string reach a fully drawn position from which the user can shoot the bow with maximum speed and energy. The user can also draw, hold and release the string to shoot the arrow from any partial draw position, thereby not requiring the user to draw and hold the string in the full draw position before shooting.
Pulley braking systems, as depicted in U.S. Pat. No. 6,032,660 have been developed that impart friction onto the pulley or cam of the bow system and lower the amount of force a user must place on the bow to hold the bow at partial draw or full draw. Although these pulley braking systems allow the user to retain the bow at partial or full draw with less force, the pulleys are located on the limb(s) of the bow, and thus the brake caliper of the pulley braking system is also located on the limb(s) of the bow. Positioning the braking system on the limbs of the bow increases the weight of the limbs, which in turn reduces the amount of force that a rebounding or recoiling limb can impart on the bowstring when the bowstring is released from full draw. What is needed is a device that allows a user to reduce or relieve tension needed to hold the bow string at partial or full draw position while maintaining a higher performance out of the bow.